FINBIZTOOLS
How Is EMI Calculated?
An equated monthly instalment, or EMI, is a level scheduled payment used to repay a reducing-balance loan over a chosen tenure. Each payment contains interest and principal, although their proportions change over time.
The inputs
- Principal (P): the opening loan amount.
- Monthly rate (r): the nominal annual percentage divided by 12 and by 100.
- Number of payments (n): the tenure expressed in months.
The EMI formula
EMI = P × r × (1 + r)^n ÷ ((1 + r)^n − 1)
When the interest rate is zero, the payment is simply principal divided by the number of months. The formula assumes a fixed rate, equal monthly periods and payments made on schedule.
Worked example
For a ₹10,00,000 loan, an 8.5% nominal annual rate and 120 monthly payments, the monthly rate is 0.085 ÷ 12. Substituting those values gives an EMI of approximately ₹12,398.57. Across 120 payments, estimated repayment is about ₹14,87,828.40 and estimated interest is about ₹4,87,828.40. Small differences can arise from lender rounding and payment dates.
Principal and interest through time
Interest for a period is calculated on the outstanding balance. Early payments therefore tend to contain more interest. As principal is repaid, the balance and interest component decline. An amortization schedule shows this progression rather than treating every payment as the same mix.
How tenure changes the result
A longer tenure generally lowers the monthly payment when other inputs stay constant, but keeps principal outstanding longer and can increase total interest. A shorter tenure generally raises the payment and can reduce total interest. Use the EMI Calculator to compare scenarios one input at a time.
What a simple estimate excludes
Processing fees, insurance, taxes, irregular dates, changing rates, late charges, prepayments and lender-specific rounding may not be included. Read the lender’s repayment schedule and agreement for the contractual amount.
Frequently asked questions
Is EMI the total cost of a loan?
No. EMI describes scheduled repayments; fees and other charges may add to the cost.
Does a floating rate keep the same EMI?
Not necessarily. A lender may change the EMI, tenure or both under the agreement.
Educational disclaimer
Results are informational estimates, not a loan offer or financial advice.
From annual rate to monthly rate
For the standard reducing-balance formula, the nominal annual percentage is divided by 12 and then by 100. For example, 9% becomes a monthly decimal rate of 0.0075. This convention may differ from a lender’s daily-interest, reset-date or effective-rate method, so a calculator result should be compared with the lender’s schedule.
Worked repayment check
For principal ₹5,00,000, a hypothetical annual rate of 9% and 60 monthly payments, the formula produces an EMI of approximately ₹10,379.18. Multiplying by 60 gives total repayment of about ₹6,22,750.80, so total interest is about ₹1,22,750.80. Minor paise differences can arise when each instalment is rounded separately.
How tenure changes the result
With the same principal and rate, a longer tenure normally lowers each EMI but keeps principal outstanding for longer, increasing total interest. A shorter tenure normally raises the monthly commitment while reducing time-based interest. Use the EMI Calculator to compare scenarios, then account separately for fees, insurance, prepayments and rate changes.